test: fold ported-clojure batteries into spec

Mine the remaining integration 'ported Clojure' batteries into the spec layer
and delete them (clojure-atom/control/for/logic/macros, core, logic). A broad
function-coverage diff confirmed they exercised no clojure.core fn the spec
lacked; their distinctive value was the truthiness/boolean contract, now
captured in a dedicated spec.

New/expanded spec coverage:
- spec/truthiness-spec: only nil/false are falsy (0, "", [], {}, #{} are truthy);
  not / and / or return-value & short-circuit semantics; if-not/when-not/boolean
- assert (exceptions-spec), get-validator (state-spec)

Layout now: spec 23 files / 732 cases; integration trimmed to 10 genuine
cross-cutting batteries (conformance, SCI bootstrap/runtime, jank, compile-mode,
api, namespace, bootstrap, features, systematic-coverage). conformance 218/218,
jpm test green.

test/spec/exceptions-spec.janet

@@ -17,6 +17,12 @@
   ["catch value of body" "5"
    "(try (+ 2 3) (catch :default e 0))"])
 
+(defspec "exceptions / assert"
+  ["assert true -> ok"   ":ok"    "(do (assert true) :ok)"]
+  ["assert expr -> ok"   ":ok"    "(do (assert (= 1 1)) :ok)"]
+  ["assert false throws" :throws  "(assert false)"]
+  ["assert nil throws"   :throws  "(assert nil)"])
+
 (defspec "exceptions / ex-info"
   ["ex-message"          "\"oops\""  "(ex-message (ex-info \"oops\" {}))"]
   ["ex-data"             "{:k 1}"    "(ex-data (ex-info \"oops\" {:k 1}))"]

test/spec/state-spec.janet

@@ -21,7 +21,8 @@
   ["add-watch fires"    "1"      "(let [a (atom 0) seen (atom 0)] (add-watch a :k (fn [k r o n] (reset! seen 1))) (reset! a 5) @seen)"]
   ["remove-watch"       "0"      "(let [a (atom 0) seen (atom 0)] (add-watch a :k (fn [k r o n] (swap! seen inc))) (remove-watch a :k) (reset! a 5) @seen)"]
   ["set-validator! ok"  "5"      "(let [a (atom 0)] (set-validator! a number?) (reset! a 5) @a)"]
-  ["set-validator! rejects" :throws "(let [a (atom 0)] (set-validator! a pos?) (reset! a -1))"])
+  ["set-validator! rejects" :throws "(let [a (atom 0)] (set-validator! a pos?) (reset! a -1))"]
+  ["get-validator"      "true"   "(let [a (atom 0)] (set-validator! a number?) (fn? (get-validator a)))"])
 
 (defspec "state / volatiles & delays"
   ["volatile! deref"    "0"      "(let [v (volatile! 0)] @v)"]

test/spec/truthiness-spec.janet

@@ -0,0 +1,61 @@
+# Specification: truthiness & boolean logic.
+# The core Clojure rule: ONLY nil and false are logically false; every other
+# value — including 0, 0.0, "", and empty collections — is logically true.
+(use ../support/harness)
+
+(defspec "truthiness / if (only nil & false are falsy)"
+  ["nil is falsy"       ":f"   "(if nil :t :f)"]
+  ["false is falsy"     ":f"   "(if false :t :f)"]
+  ["zero is truthy"     ":t"   "(if 0 :t :f)"]
+  ["zero float truthy"  ":t"   "(if 0.0 :t :f)"]
+  ["empty string truthy" ":t"  "(if \"\" :t :f)"]
+  ["empty list truthy"  ":t"   "(if (list) :t :f)"]
+  ["empty vector truthy" ":t"  "(if [] :t :f)"]
+  ["empty map truthy"   ":t"   "(if {} :t :f)"]
+  ["empty set truthy"   ":t"   "(if #{} :t :f)"]
+  ["number truthy"      ":t"   "(if 42 :t :f)"]
+  ["string truthy"      ":t"   "(if \"x\" :t :f)"]
+  ["keyword truthy"     ":t"   "(if :kw :t :f)"]
+  ["symbol truthy"      ":t"   "(if (quote abc) :t :f)"]
+  ["coll truthy"        ":t"   "(if [1 2] :t :f)"]
+  ["map truthy"         ":t"   "(if {:a 1} :t :f)"]
+  ["if no else -> nil"  "nil"  "(if false :t)"])
+
+(defspec "truthiness / not"
+  ["not nil"            "true"  "(not nil)"]
+  ["not false"          "true"  "(not false)"]
+  ["not zero"           "false" "(not 0)"]
+  ["not empty vector"   "false" "(not [])"]
+  ["not empty string"   "false" "(not \"\")"]
+  ["not number"         "false" "(not 42)"]
+  ["not true"           "false" "(not true)"])
+
+(defspec "truthiness / and"
+  ["empty is true"      "true"  "(and)"]
+  ["single value"       "5"     "(and 5)"]
+  ["all truthy -> last" "3"     "(and 1 2 3)"]
+  ["stops at false"     "false" "(and 1 false 3)"]
+  ["stops at nil"       "nil"   "(and 1 nil 3)"]
+  ["false alone"        "false" "(and false)"]
+  ["nil alone"          "nil"   "(and nil)"]
+  ["zero is truthy"     "0"     "(and 1 0)"])
+
+(defspec "truthiness / or"
+  ["empty is nil"       "nil"   "(or)"]
+  ["first truthy"       "1"     "(or 1 2)"]
+  ["skips nil/false"    "5"     "(or nil false 5)"]
+  ["all falsy -> last"  "false" "(or nil false)"]
+  ["nil chain -> false" "false" "(or nil nil nil false)"]
+  ["zero is truthy"     "0"     "(or 0 1)"]
+  ["false alone"        "false" "(or false)"])
+
+(defspec "truthiness / if-not & boolean"
+  ["if-not false"       ":yes"  "(if-not false :yes :no)"]
+  ["if-not truthy"      ":no"   "(if-not 0 :yes :no)"]
+  ["when-not nil"       "1"     "(when-not nil 1)"]
+  ["when-not truthy"    "nil"   "(when-not 5 1)"]
+  ["boolean of nil"     "false" "(boolean nil)"]
+  ["boolean of false"   "false" "(boolean false)"]
+  ["boolean of 0"       "true"  "(boolean 0)"]
+  ["boolean of value"   "true"  "(boolean :x)"]
+  ["true?/false?"       "true"  "(and (true? true) (false? false) (not (true? 1)))"])